123231023521 has 2 divisors, whose sum is σ = 123231023522. Its totient is φ = 123231023520.

The previous prime is 123231023477. The next prime is 123231023543. The reversal of 123231023521 is 125320132321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 118942214400 + 4288809121 = 344880^2 + 65489^2 .

It is a cyclic number.

It is not a de Polignac number, because 123231023521 - 2¹³ = 123231015329 is a prime.

It is a super-4 number, since 4×123231023521⁴ (a number of 45 digits) contains 4444 as substring.

It is not a weakly prime, because it can be changed into another prime (123231023581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61615511760 + 61615511761.

It is an arithmetic number, because the mean of its divisors is an integer number (61615511761).

Almost surely, 2^123231023521 is an apocalyptic number.

It is an amenable number.

123231023521 is a deficient number, since it is larger than the sum of its proper divisors (1).

123231023521 is an equidigital number, since it uses as much as digits as its factorization.

123231023521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 25.

Adding to 123231023521 its reverse (125320132321), we get a palindrome (248551155842).

The spelling of 123231023521 in words is "one hundred twenty-three billion, two hundred thirty-one million, twenty-three thousand, five hundred twenty-one".